According to different causative factors, hair damage can be divided into the following types: 1) physical damage: daily combing and straightening of hair, during which pulling force and friction result in the delamination and peeling off of cuticle scales covered on hair surface; 2) Chemical damage: substances such as perm agent, hair dye and decolorizer destroy the hair grease layer, and penetrate underneath the hair cuticle scales into hair cortex, causing breakage of keratin disulfide bonds, and resulting in decline of hair hydrophobicity, strength and flexibility; 3) thermal damage: hair drier or electric perm evaporates moisture, causing hair dry and brittle, broken; 4) light damage and natural aging: ultraviolet radiation in natural light causes cystine, tyrosine and tryptophan etc. photodegrade in hair keratin, and furthermore leading to hair damage and aging.
Donkey-hide gelatin is described as “sweet in taste, is to Lung, Liver and Kidney Channel Tropism”. According to “Compendium of Materia Medica”: “Donkey-hide gelatin is generally just complementing Xue and Qi, therefore it can clear away the Heatin the lung and enrich Yin, thereby treating various diseases . . . . Donkey-hide gelatin′ssweetness can be used to complement Yin and Xue . . . ”. Donkey-hide gelatin is the captain of complementingXue, it complements Xue in five zang organs, nourishing Yin in five zang organs, it can be used for complementing various deficiencies in Xue. When blood is plentiful, hair can then be nourished and glossy. The innovation of the present invention is to utilize the function of Donkey-hide gelatin to complement blood, nourish hair and skin and make them lustrous, proposing an application of Donkey-hide gelatin or deep processed material from Donkey-hide gelatin in the production of compositions to improve hair quality. Said improvement of hair quality embodies in two aspects described below: 1) to improve the smoothness and gloss of normal hair, and promote hair growth; 2) to repair hair damage due to physical factors (such as straightening), chemical factors (such as hair coloring and de-coloring) and heating (e.g., perm). No reports have been seen on applications of Donkey-hide gelatin or deep processed material from Donkey-hide gelatin in the manufacture of compositions for improvement of the hair quality.